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Coordinating Zirconium Nodes in Metal-Organic Framework with Trifluoroacetic Acid for Enhanced Lewis Acid Catalysis

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Chemical Research in Chinese Universities 2022年第5期38卷 1301-1307页

作者： WANG Wenyang LIU Hanlin YANG Caoyu FAN Ting CUI Chengqian LU Xiaoquan TANG Zhiyong LI Guodong Department of Chemistry School of ScienceTianjin UniversityTianjin 300072P.R.China CAS Key Laboratory of Nanosystem and Hierarchical Fabrication CAS Center for Excellence in NanoscienceNational Center for Nanoscience and TechnologyBeijing 100190P.R.China School of Nanoscience and Technology University of Chinese Academy of SciencesBeijing 100049P.R.China Key Laboratory of Bioelectrochemistry&Environmental Analysis of Gansu Province College of Chemistry&Chemical EngineeringNorthwest Normal UniversityLanzhou 730070P.R.China

Regulating Lewis acid sites with well-defined electronic state and steric environment is still challenging for achieving high catalytic efficiency.Here we show coordinating zirconium nodes in the typical metal-organic framework known as MOF-545 with the monocarboxylate modulators including trifluoroacetic acid(TFA)or benzoic acid(BA)over meso-tetra(4-carboxyphenyl)-porphine(H_(2)TCPP),denoted as MOF-545-TFA or MOF-545-BA.Impressively,MOF-545-TFA shows the significantly enhanced performance for the catalytic ring-opening reaction of various epoxides with alcohols and good recyclability at 40°C in respect with MOF-545-BA and ZrO_(2).This mainly originates from the stronger Lewis acidity and more active zirconium sites induced by the electron-withdrawing TFA,resulting in the increased ability for activation of epoxides.This modulation approach is promising for enlarging the toolbox to extend the MOFs-based Lewis acid catalysis.

关键词： Metal-organic framework Active zirconium site Trifluoroacetic acid Epoxide ring-opening Modulator effect

FeF_(x) and Fe_(2)ZrO_(5) Co-modified hematite for highly efficient solar water splitting

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Journal of Energy Chemistry 2022年第6期31卷 414-420,I0012页

作者： xiaoquan Zhao Cheng lu Shuo Li Yufeng Chen Gaoteng Zhang Duo Zhang Kun Feng Jun Zhong Institute of Functional Nano and Soft Materials Laboratory(FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials&DevicesSoochow UniversitySuzhou 215123JiangsuChina State Key Laboratory of Radiation Medicine and Protection School of Radiation Medicine and ProtectionSoochow UniversitySuzhou 215123JiangsuChina

Hematite is an excellent catalyst for photoelectrochemical (PEC) water splitting but its performance has been highly limited by poor conductivity and high charge recombination.Here by a Zr-based treatment to create bulk Fe_(2)ZrO_(5) in hematite and a F-based treatment to form an ultrathin surface FeF_(x) layer,the charge transfer can be highly improved and the charge recombination can be significantly suppressed.As a result,the FeF_(x) /Zr-Fe_(2)O_(3) photoanode presents an enhanced PEC performance with a photocurrent density of 2.43 m A/cm^(2)at 1.23 V vs.RHE,which is around 3 times higher than that of the pristine Fe_(2)O_(3) .The FeF_(x) /Zr-Fe_(2)O_(3) photoanode also shows a low onset potential of 0.77 V vs.RHE (100 mV lower than the pristine hematite).The performance is much higher than that of the sample treated by Zr or F alone,suggesting the synergistic effect between bulk Fe_(2)ZrO_(5) and surface FeF_(x) .By coupling with the FeNiOOH co-catalyst,the final photoanode can achieve a high photocurrent density of 2.81 mA/cm^(2) at 1.23 V vs.RHE.The novel design of Zr and F co-modified hematite can be used as a promising way to prepare efficient catalysts for solar water splitting.

关键词： Hematite Fe_(2)ZrO_(5) Fluorination Solar water splitting

Density functional theory calculation on the C―H bond insertion reaction of dibromocarbene with acetaldehyde

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Chinese Science Bulletin 2008年第5期53卷 718-726页

作者： LI ZhiFeng YANG Sheng lu LingLing LU Xiaoquan KANG JingWan College of Life Science and Chemistry Tianshui Normal University '13anshui 741001 China Gansu Key Laboratory of Polymer Materials College of Chemistry and Chemical Engineering Northwest Normal University Lanzhou 730070 China

The insertion reaction mechanism of CBr_2 with CH_3CH_O has been studied by using the B3LYP/6-31G(d) method. The geometries of reactions, transition state and products were completely optimized. All the energy of the species was obtained at the CCSD(T)/6-31G(d) level. All the transition state is verified by the vibrational analysis and the internal reaction coordinate (IRC) calculations. The results show that the propionaldehyde (~HP1) is the main product of CH_2 insertion with CH_3CH_O. The calculated results indicated that all the major pathways of the reaction were obtained on the singlet potential energy surface. The singlet CBr_2 not only can insert the C_α-H [reaction I(1)]) but also can react with C_β-H [reaction II(1)]. The statistical thermodynamics and Eyring transition state theory with Wigner correc- tion are used to study the thermodynamic and kinetic characters of I(1) and II(1) in temperature range from 100 to 2200 K. The results show that the appropriate reaction temperature rang is 250 to 1750 K and 250 to 1600 K at 1.0 atm for I(1) and II(1) respectively. The rate constant and equilibrium constant are distinct in the range from 250 to 1000 K so that I(1) more easily occurs, while the reactions are not selected in the temperature range of 1000-1600

关键词：密度泛函理论二溴化碳乙醛碳-氢键结合反应

Quantum chemical and topological study on the insertion reaction of dichlorcarbene with acetaldehyde

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Chinese Science Bulletin 2008年第15期53卷 2287-2296页

作者： LI ZhiFeng ZHU YuanCheng YANG Sheng LU Xiaoquan College of Life Science and Chemistry Tianshui Normal University Tianshui 741001 China Gansu Key Laboratory of Polymer Materials College of Chemistry and Chemical Engineering Northwest Normal University Lan- zhou 730070 China

The insertion reaction mechanisms of siglet and striglet CCl2 with CH3CHO have been studied by using the DFT, NBO, CCSD(T) and AIM method. The geometries of reactions, transition state and products were completely optimized by B3LYP/6-31G(d). All the energy of the species was obtained at the CCSD(T)/6-31G(d,p) level. The calculated results indicated that all the major pathways of the reaction were obtained on the singlet potential energy surface. The singlet CCl2 can not only insert the Cα—H (reaction I) but also can react with Cβ—H (reaction Ⅱ). There are three main existing pathways and the products are P1 (CH3COHCCl2), P2 (CH2COHCHCl2) and P4[CHCl2CHCHOH] respectively. Reaction Ⅱ happens more easily according to the energy changes and the barrier in rate-controlling step. In addi-tion, the important geometries in domain pathways have been studied by AIM theory. And also, the en-ergy changes of H in the inserted C—H bond have been investigated.

关键词：量子化学插入反应 CCl2 DFT NBO

A co-activation strategy for enhancing the performance of hematite in photoelectrochemical water oxidation

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Chinese Chemical Letters 2021年第7期32卷 2279-2282页

作者： Boyao Xie Xingming Ning Shuoming Wei Jia Liu Jimei Zhang xiaoquan lu Tianjin Key Laboratory of Molecular Optoelectronic Science Department of ChemistrySchool of ScienceTianjin UniversityTianjin 300072China State Key Laboratory of Separation Membranes and Membrane Processes School of Chemistry and Chemical EngineeringTiangong UniversityTianjin 300387China

Hematite(α-Fe_(2)O_(3))is a promising photoanode for photoelectrochemical(PEC)water splitting.However,the severe charge recombination and sluggish water oxidation kinetics extremely limit its use in photohydrogen conversion.Herein,a co-activation strategy is proposed,namely through phosphorus(P)doping and the loading of CoAl-layered double hydroxides(CoAl-LDHs)cocatalysts.Unexpectedly,the integrated system,CoAl-LDHs/P-Fe_(2)O_(3) photoanode,exhibits an outstanding photocurrent density of 1.56 mA/cm^(2) at 1.23 V(vs.reversible hydrogen electrode,RHE),under AM 1.5 G,which is 2.6 times of pureα-Fe_(2)O_(3).Systematic studies reveal that the remarkable PEC performance is attributed to accelerated surface OER kinetics and enhanced carrier separation efficiency.This work provides a feasible strategy to enhance the PEC performance of hematite photoanodes.

关键词： Photoelectrochemical Phosphorus doping Charge separation CoAl-LDHs Hematite

Density functional theory study on the insertion reaction mechanism of dibromocarbene with formaldehyde

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Chinese Science Bulletin 2007年第15期52卷 2035-2041页

作者： LI ZhiFeng luE LingLing KANG JingWan LU Xiaoquan College of Life Science and Chemistry Tianshui Normal University Tianshui 741001 China Gansu Key Laboratory of Polymer Materials College of Chemistry and Chemical Engineering Northwest Normal University Lanzhou 730070 China

The insertion reaction mechanism of CBr2 with CH3CH2O has been studied by using the B3LYP/6-311G(d) and CCSD(T)/6-311G(d) at single point. The geometries of reactions,transition state and products were completely optimized. All the transition state is verified by the vibrational analysis and the internal re-action coordinate (IRC) calculations. The results show that reaction (1) is the dominant reaction path,which proceeds via two steps: i) two reactants form an intermediate (IM1),which is an exothermal re-action of 8.62 kJ·mol?1 without energy barrier; ii) P1 is obtained via the TS1 and the H-shift,in which the energy barrier is 44.53 kJ·mol?1. The statistical thermodynamics and Eyring transition state theory with Wigner correction are used to study the thermodynamic and kinetic characters of this reaction in temperature range from 100 to 2200 K. The results show that the appropriate reaction temperature ranges from 200 to 1900 K at 1.0 atm,in which the reaction has a bigger spontaneity capability,equi-librium constant (K) and higher rate constant (k).

关键词：密度函数甲醛插入反作用热力学

Exosome-Coated Zeolitic Imidazolate Framework Nanoparticles for Intracellular Detection of ATP

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Chinese Journal of Chemistry 2021年第8期39卷 2107-2112页

作者： Wenxing Lv Ziwei Han Yike Li Yanjuan Huang Jiashu Sun xiaoquan lu Chao Liu Tianjin Key Laboratory of Molecular Optoelectronic Sciences Department of ChemistrySchool of ScienceTianjin UniversityTianjin 300072China Beijing Engineering Research Center for BioNanotechnology CAS Key Laboratory of Standardization and Measurement for NanotechnologyCAS Center for Excellence in NanoscienceNational Center for Nanoscience and TechnologyBeijing 100190China School of Future Technology University of Chinese Academy of SciencesBeijing 100049China Key Laboratory of Bioelectrochemistry and Environmental Analysis of Gansu Province College of Chemistry and Chemical EngineeringNorthwest Normal UniversityLanzhouGansu 730070China

The intracellular delivery of metal-organic frameworks(MOFs)encapsulated with functional biomolecules represents a promising av-enue in the field of biomedicine and biosensing.To improve the cellular uptake efficiency of MOFs,here we report the fabrication of cancer cell-derived exosome membra ne(EM)-coated zeolitic imidazolate framework-8(EM-ZIF-8)nan oparticles by using a microfluidic son ication device.

关键词： ATP Exosome Metal-organic frameworks Microreactors Nan oparticles

A hybrid monolithic column based on flower-shaped zeolitic imidazolate framework for efficient capillary microextraction of brominated flame retardants

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Chinese Chemical Letters 2021年第10期32卷 3199-3201页

作者： Xuemei Wang Xinglan Cui Hong Ji Fangbing Wang Yacong Liu Xinzhen Du xiaoquan lu Key Laboratory of Bioelectrochemistry&Environmental Analysis of Gansu Province College of Chemistry and ChemicalEngineeringNorthwest Normal UniversityLanzhou 730070China

A novel flower-shaped zeolitic imidazolate framework(ZIF) doped organic-inorganic hybrid monolithic column(ZIF-HMC) was prepared by a simple sol-gel "one-step" method and utilized for efficient capillary microextraction(CME) of four brominated flame retardants.The prepared monolithic was characterized by Fourier transform infrared,scanning electron microscopy,X-ray photoelectron spectroscopy,energy disperse spectroscopy,and N_(2) adsorption-desorption.The parameters of CME were optimized by orthogonal array design.Under the optimal conditions,the ZIF-HMC showed excellent extraction efficiency,the limit of detection(LODs) and the limit of quantification(LOQs) were in the range of0.52$3.1 mg/L and 1.7$10 mg/L,respectively,and the proposed method demonstrated good recovery(88.8%–116.6%) with the RSD less than 13.6% and a reusability of at least 30 times.The ZIF-HMC possessed great potential for separating organic pollutants and the strategy used here could be extended to prepare other derivatized HMC functionalized monoliths.

关键词： Capillary microextraction Brominated flame retardants Hybrid monolithic column Zeolitic imidazolate framework

Tungsten oxide nanowires and polyaniline hybrid film-based electrochromic device with multicolor display and enhanced capacitance

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Chinese Chemical Letters 2023年第11期34卷 275-279页

作者： Yanan Chen Jiao Lei Yanling Zhai Zhijun Zhu Weitai Wu xiaoquan lu Institute of Molecular Metrology College of Chemistry and Chemical EngineeringQingdao UniversityQingdao 266071China Institute of Hybrid Materials National Center of International Research for Hybrid Materials TechnologyNational Base of International Science&Technology CooperationCollege of Materials Science and EngineeringQingdao UniversityQingdao 266071China State Key Laboratory of Physical Chemistry of Solid Surfaces Xiamen UniversityXiamen 361005China

Electrochromic devices(ECDs)have exhibited promising applications in the fields of energy-saving intelligent buildings and next-generation displays because of their simple structure,low power consumption,and multicolor displays.W_(18)O_(49)/polyaniline(PANI)hybrid films are prepared and assembled to ECDs.Compared with pure PANI and W_(18)O_(49) films,the hybrid film exhibits superior electrochemical and electrochromic performance,including high optical modulation(70.2%),large areal capacity(79.6 mF/cm^(2)),and good capacitance retention.The excellent electrochemical and electrochromic performance is ascribed to the formation of the donor(PANI)-acceptor(W_(18)O_(49))pair,the porous structure in the nanowires,and the large surface area,which enhance electron delocalization of the W_(18)O_(49)/PANI,improve the ion diffusion rate,and increase the charge storage sites.Furthermore,benefitting from the outstanding optical,electrical,and multifunctional properties,the W_(18)O_(49)/PANI hybrid film-based ECD platform is expected to play an important role in electrochromism and energy storage.

关键词： W_(18)O_(49)/PANI Electrochromism Multifunctional devices Multicolor Energy storage